﻿CHINA AQI DATASET 

Original Source:   http://www.aqicn.org

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License: free for academic research, no commercial use, resale, or redistribution permitted.
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Published: Dec 2016
Editor: Lex Berman
Programming:  Zhenyang Hua, Fei Carnes
CHGIS, Center for Geographic Analysis

Email: chgis@fas.harvard.edu
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Distribution URL: https://dataverse.harvard.edu/dataverse/aqicn

Online Reference Pages: http://aqi.cga.harvard.edu/china/about/


Character set encodings:  

   UTF8  (https://en.wikipedia.org/wiki/UTF-8)


ABSTRACT:   AQI air quality observations from ground monitoring stations in China are collected and stored PostGresql (three times each day).  The AQI values are coded to Locations which have mappable x, y coordinates in a seperate cumulative locations table.

PERIOD OF DATA COLLECTION:  2014-02  to 2016-02

Total number of observations ~ 2.5 million

The CUMULATIVE files are:

locations.csv (showing all the locations with unique x, y values found during the research period)
observations.csv (which are the cumulative readings from each station...  these are captured three times per day, with each row being one station at a particular timestamp)


Subsequent data collection was set up for hourly readings from www.pm25s.com   
(see cumulative tables for that dataset: Distribution URL: https://dataverse.harvard.edu/dataverse/china_pm25s)


Character set encoding:  
   UTF8  (https://en.wikipedia.org/wiki/UTF-8)



Data Dictionary:

FIELD_NAME	DESC_UNITS
LocatID	Location ID generated by unique latitude-longitude pairs for each monitor location
StationName	Station Name as defined by the monitor owner  (might change, might not be unique)
ChName	Chinese language station name (UTF8 encoding)
Latitude	Latitude North in decimal degrees WGS84
Longitude	Longitude East in decimal degrees WGS84
PM2.5	Particulate Matter 2.5 micron diameter   µg/m3 (micrograms per cubic metre)
PM10	Particulate Matter 10 micron diameter  µg/m3 (micrograms per cubic metre)
O3	Ozone   pphm (parts per hundred million)
NO2	NOX  NitrogenDioxide   pphm (parts per hundred million)
SO2	SOX  SodiumDioxide  pphm (parts per hundred million)
CO	CarbonMonoxide  ppm (parts per million)
Temperature	degrees Celsius
DewPoint	degrees Celsius
Pressure	millibars
Humidity	absolute humidity in grams/meter3
Wind	km / hour
UMT_time	data collection time Greenwich Meat Time
